1,234. Castration

191:4 We are not allowed to make a bird sit on eggs that are not of its species. This is considered tormenting animals.

191:5 It is prohibited to castrate a human, an animal – either wild or domesticated – or a bird, whether kosher or non-kosher, both in and out of Israel. One who performed castration was liable to the penalty of lashes. It is likewise prohibited even to give an emasculating potion to a man or to any other male creature.